Recording chart support



Oct. 13,1931.\ Kw. H. PEARCE 1,826,895

` RECORDING CHART SUPPORT u Filed Nov. 5, 1926 QJ INVLMOR f 6,Q MM TER/f PLC/mir l BY 4 Patented oct. 13, 1931 UNITED STATES PATENT OFFICE WALTER H. PEARCE, F PHILADELPHIA, PENNSYLVANA, ASSIGNOR T0 THE BROWN INSTRUMENT COMPANY, OF PHILADEL PENNSYLVANIA PHIA, PENNSYLVANIA, A CORPORATION RECORDING CHART snrron'r Application filed Novembei` Mypresent invention relates Ato recording instruments of the type in which the record chart is a disc rotated by suitable time cont-rolled mechanism; and the general object chart support with simple chart centering.

and holding portions which will permit the chart to be readily and eiiectively ,secured to the support in the proper posit-ion relative to the latter, and which will permit the ready removal of the chart from said support without requiring relative movement of the chart engaging provisions which may ormrigidly connecting parts of the rotating chart support. v

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, its Aadvantages and speciiic objects attained with its use, reference should be had to the accompanying drawings and descriptive matter in which I have illustrated Vand described preferred embodiments of my ini vention.

i ing a chart;

Of the drawingsz- Fig.`1j is afront elevation.;

Fig. 2 is aside elevation in section illustrating one stage in the operation yoft mount- Figs. 3 and 4g'are views taken similarly to Fig. 2v illustrating successive stagesin-the chart mounting operation;

Fig. Ais a 'view .taken similarly to Fig. 2

l in its normal position on the chart support;

' and' instrument of the usual type used in recording variations in temperatures or pressures, in which a pen or other marking element B moving .in response to variations in the value of the quantity measured, records such variations on a paper disc chart Gse- 5, 1926. Serial No.'146,422-.

cured to a chart support rotated by a suitable timing mechanism.

The drivin mechanism may comprise any usual or suita le form of motor, (not shown) for continuously rotating at the proper speed the shaft D which carries the chart support. body with a rear sleeve portion E surrounding the shaft D and rigidly secured thereto by a pin E2. j Projecting from the front J face Esci the bod of the member E is a post E4 which is rigi ly 'connected to land may be integral withthebody portion of thesupport and is co-a'xial with the shaft D. The

. post E* comprises a cylindrical body or shank portion and an enlarged head or button portion E5. The outer end of the head E is rounded or tapered to facilitate'itsentrance in lthe central aperture C of the chart disc C when the ,latter is` formed with such an aperture and is put in place as hereinafter described. The support is provided with one, or,`preferably as shown, a plurality of pins F projecting outwardly from the face E3 at some radial distance from the post E4'. The pins F have pointed ends F and puncture the chart disc C when the latter is put in p aperture receivingthe support and has its front face in substantially the same plane as the support.

In mounting the chart C on the chart sup-.

l port the chart is centered by entering the rounded or taperedend of the enlarged head E5 in the aperture C and thereafter the chart is moved inward until its central portion envgages the fa'ce E3 as shown in Fig. 5. Figs. 2, 3, and 4 illustrate different relative positions of the support and chart as the latter is being put in place. Before the chart is punctured by the'pins F, it is adjusted angularly about the axis of the support, as required to bring the chart into the position in which the marking element B and the usual time interval lines on the chart are in the proper time relation.

The chart 'opening in diameter than the enlarged post head E",

The latter,.as shown, is a disc-like Cl is initially smaller and in practice the opening C may advantageously he slightly smaller in diameter than the body of the post E4. With such relative diameter of the chart opening C', the chart material will break or tear along short lines C2 generally radial to the axis of the hole C',

unless the chart is initially formed as it may be with cuts projecting radially outward from Athe margin of the opening Cf along the lines generally similar to the lines C2 so as to form `chart at the margin of the opening C', and if, j as I consider preferable in all cases, the initial the chart initially .with resilient tongues which bend outward when the chart is pushed home over the post E4.

In any event, when the chart C is mounted on the chart support with the body of the chart at the margin of theopenng C bearingagainst the front face of the disc-like portion Es of the chart support, the enlarged head portion E5 overhangs the' portion of the diameter of the opening C is less than the diameter ofthe shank portion of the post, the portion of the chart material immediately adjacent the post will be outturned as shown in Fig. 5, and will be in more or less snug frictional engagement with the shank of the post E4. In consequence, .the chart will not only be held against accidental removal from the chart support but will be accurately centered on the latter, and the chart may be readily removed when chart replacement is necessary without subjecting the chart to .undue force. The pin, or pins, F, form an effective driving connection between the chart and the chart support E, and theufact that the openings inthe chart receiving the pins IF are formed] by the latter when the lchart is put in place, contributes to a desirable rigidity, so as to speak, in the connection between the chart and the chart support. The pin or pins F also tend to prevent 'any unsymmetrical. enlargement of the opening C in the chart C, when the latter is forced over" the head E, and thus contribute to the accurate centering of the chart in its working position.

The chart securing provisions illustrated and described are simple and effective ,and for-m a satisfactory solution of a problem which has led to the development and extensive us`e of the so-called non-removable chart knobs to avoid the inconvenience resulting from the frequent loss of chart knobs experi- V`out departing from t enced with the still earlier type-of construction in which the chart is removably secured in place by a removable knob in threaded engagement with the rotating chart su port.

The so-called non-removable chart kno s are especially important when the invention is used in a combined indicating and recording instrument comprising an index hand swinging across'the axis ofthe rotating chart support. The distin ishing characteristic of the present inventlon is that .the chart penetrating post, including its body portion and its enlarged head E5, is in operatively fixed relation with the chart driving member. In describing the post here and in the appended claims as in operatively fixed relation with the chart drivlng member, I mean to distinguish from the chart supporting and driving constructions of the prior art in which the post includes or has detachably secured thereto a clamping part which is movable relative to another portion or portions of the chart supporting and driving means to secure a chart in place and to permit the latter to be removed.

While in accordance with the provisions of the statutes, I have illustrated and described the best form of embodiment of my invention now known to me, it will be apparent -to those skilled in the art that changes may be made in the form of the apparatus disclosed withe spirit of my invention as set forth in the apended claims and that in'some cases certain eatures of my invention may be used to advantage without a corresponding use of other features.

Havingnow described my invention, what I claim as new and desire to secure by Letters Patent is 1. In recording apparatus, chart holding and rotating means comprising a rotatable driving member having a body portion and having an outer end portion 1n operatively fixed relation thereto and connected to said body portion by a shank smaller in diameter than said end portion whereby when said end portion is forced through a chart aperture snugly receiving said shank said chart will have its front side overhung at the margin of saido ening by said end portion, and one or more'c art penetrating portions of a length intermediate those of the post and its shank portion projecting from said body portion alongside saidpost.

2. In recording apparatus, chart holding and rotating means comprising a rotatable driving member having a body portion andk a chart penetrating post projecting from said body portion and in operatively fixed relation to engage and penetrate said chart when the ture snugly receiving said shank said chart l Will have its front side overhung at the margin of said opening by said end portion, and.

one or more pointed chart puncturing parts projecting from said body portion at some radial distance from said post and of a length latter is forced over said post.

3. In recording apparatus, chart holding and rotating means comprising a rotatable driving member having a body portion secured thereto and a chart penetrating post member projecting from said body portion and in operatively fixed relation thereto and larger in diameter than the central aperture of a. chart adapted to be centered thereonand pin members shorter than said post secured to said body portion near the post and arranged to assist. lin centering and connecting said chart to said body portion for rotation therewith.

4. In recording apparatus, chart holding and rotating means comprising a rotatable driving member having a body portion secured thereto, achart penetrating post member projecting from said body portion` and in operatively ixed relation thereto and larger in diameter than the central aperture of a chart adapted to be centered thereon, and chart penetrating pin members secured to said body portion and of a length adapted to aid in centering and connecting said chart to said body portion for rotation therewith, and one` of said members having an undercut outer end portion.

5. In recording apparatus, chart holding and rotating means comprising a rotatable driving member having a 'body portion secured thereto, a stationary chart supporting' plate surrounding said body portion, a chart centering post projecting from said vbody portion and in operatively fixed relation thereto and having a diameter not less lthan that of the central aperture of a chart adapted to be centered thereon and a plurality of `pins mountedion said body member about said post and of a length to engage and penetrate a chart centered on said ost and cause said chart to rotate with said body portion.

Signed at Philadelphia, in the county of Philadelphia and State of Pennsylvania, this 3d day of November, A. 11.1926.

e WALTER H. PEARCE. 

